1. Field of the Invention
The present invention relates to a motor vehicle steering wheel provided with controls to operate corresponding devices of the motor vehicle.
The present invention is advantageously applied to a steering wheel provided with controls to operate the turn indicators, to which the following description will explicitly refer without losing in generality.
2. Description of the Related Art
In order to circulate on public roads, a motor vehicle is to be provided with light turn indicators (the so-called “turn signals”), which signal the intention to modify the direction of the motor vehicle.
The light turn indicators are traditionally operated (that is, switched on or off) by means of a control, which is mounted on the steering column (normally on the left side of the steering column) and is vertically movable (that is, the control is pushed upwards to operate the right turn indicators and is pushed downwards to operate the left turn indicators).
It has been recently suggested to arrange the control of the turn indicators on the steering wheel so that the driver can operate the turn indicators without ever removing his/her hands from the steering wheel (in particular when the steering wheel is already partially turned to the left or to the right). In particular, the steering wheel comprises a central hub which is mounted so as to rotate on the steering column, an outer crown which is suited to be held by the driver and at least two spokes which connect the outer crown to the central hub and are arranged symmetrically to the right and to the left of the central hub; the control of the turn indicators comprises two controls, which are arranged on opposite sides of the central hub on the corresponding spokes, and the control arranged to the left (when the steering wheel is in the neutral position corresponding to a straight trajectory) obviously operates the left turn indicators and the control arranged to the right (when the steering wheel is in the neutral position corresponding to a straight trajectory) obviously operates the right turn indicators.
However, certain drivers have found the above-described conformation of the turn indicator controls on the steering wheel not to be completely ergonomic, because, when the steering wheel is rotated, confusion may arise as to which control operates the left turn indicators and which one operates the right turn indicators. In other words, when the steering wheel is in the neutral position (corresponding to a straight trajectory), the control which operates the left turn indicators is to the left of the hub and the control which operates the right turn indicators is to the right of the central hub; instead, when the steering wheel is rotated by 90°, the controls which operate the turn indicators are up and down relative to the central hub and when the steering wheel is rotated by 180°, the control which operates the left turn indicators is to the right of the hub and the control which operates the right turn indicators is to the left of the central hub. Accordingly, when the steering wheel is rotated, it is possible for the driver not to immediately and intuitively perceive which control operates the left turn indicators and which control operates the right turn indicators.
Patent Application US2008173127A1 (corresponding to Patent Application DE102005038855) describes a motor vehicle steering wheel provided with a pair of controls which are arranged at respective spokes of the steering wheel and operate the turn indicators; such controls are mounted so as to be movable in order to axially move (that is, along a direction parallel to the rotation axis of the steering wheel) in opposite directions so that an axial movement in a direction operates one turn indicator and an axial movement in an opposite direction operates the other turn indicator.